2020–2021 BCSC Basic and Clinical Science Course™
2 Fundamentals and Principles of Ophthalmology
Part I: Anatomy
Chapter 3: Cranial Nerves: Central and Peripheral Connections
The Cerebral Vascular System
The CNs can be affected by the surrounding cerebrovascular system, which includes both arterial and venous components. CN palsies can be harbingers of life-threatening conditions. Thus, it is imperative to understand the CNs’ anatomical relationships with adjacent structures. For further discussion of the cerebral vasculature and the various resultant syndromes of the CNs, see BCSC Section 5, Neuro-Ophthalmology.
Cavernous Sinus
The cavernous sinus is an interconnected series of venous channels located just posterior to the orbital apex and lateral to the sphenoid sinus and pituitary fossa. The following structures are located within the venous cavity:
Figure 3-24 shows the entry of CNs III–VI into the cavernous sinus from the midbrain. Figure 3-25 depicts the relative location of these structures in different parts of the cavernous sinus.
Excerpted from BCSC 2020-2021 series: Section 2 - Fundamentals and Principles of Ophthalmology. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.